Photocuable Ink Composition Set, Ink Jet Recording Method, and Recorded Matter

Abstract

A photocurable ink composition set includes ink composition A and ink composition B. Ink composition A contains a dendritic polymer and an monomer expressed by general formula (1): CH₂═CR¹—COO—R²—O—CH═CH—R³. Ink composition B contains a coloring agent and a monomer expressed by general formula (1). In the formula (1), R¹ represents a hydrogen atom or a methyl group, R² represents an organic moiety having a carbon number in the range of 2 to 20, and R³ represents a hydrogen atom or an organic moiety having a carbon number in the range of 1 to 11.

Description

BACKGROUND[0001]1. Technical Field[0002]The present invention relates to a photocurable ink composition set, and an ink jet recording method and recorded matter using the same.[0003]2. Related Art[0004]Photocurable ink compositions are increasingly being used for manufacture of color filters, printing on print boards and plastic materials such as plastic cards, plastic sheets, and plastic components, printing for large sign boards and outdoor and indoor advertisements, and printing of bar codes and dates.[0005]Japanese Unexamined Patent Application Publication No. 2004-99796 discloses a photocurable ink composition containing a dendrimer, which is a type of dendritic polymer. Dendritic polymers have a molecular structure in which functional groups are more closely present at the surface than general linear polymers, and are therefore expected as functional nano-polymer materials.[0006]Unfortunately, the addition of a dendritic polymer to an ink composition significantly increases th...

AI Technical Summary

Benefits of technology

[0009]Accordingly, an advantage of some aspects of the invention is that it provides a low-viscosity, safe, storage-stable, highly curable photo-curable ink composition set that can be cured to form a high quality film, and an ink jet recording method and recorded matter using the photocurable ink composition set. According to an aspect of the invention, a photo-curable ink composition set is provided which includes ink composition A containing a dendritic polymer and an monomer expressed by general formula (1): CH2═CR1—COO—R2—O—CH═CH—R3; and ink composition B containing a coloring agent and a monomer expressed by general formula (1). In general formula (1), R1 represents an hydrogen atom or a methyl group, R2 represents an organic moiety having a carbon number in the range of 2 to 20, and R3 represents a hydrogen atom or an organic moiety having a carbon number in the range of 1 to 11.

Problems solved by technology

Unfortunately, the addition of a dendritic polymer to an ink composition significantly increases the viscosity of the ink.

The increase of the viscosity may cause the ink jet head to fail the ejection of the ink.

However, low-viscosity monomers generally have low molecular weights, and often have low flash points and odors and cause skin irritation, thus having health and safety issues.

The addition of such a constituent not involved in curing reaction, however, undesirably requires additional, special treatment and increases the load of the manufacturing process.

If curing reaction is conducted before the additive is completely dried, air bubbles may be generated from the residual solvent or water by heat for polymerization, or the residual solvent or water may bleed from the cured composition to remain at the surface and cause tackiness.

In addition, many photocurable ink compositions are unstable in storage, and their viscosities are increased to gelate.

This is because the ink composition is itself reactive, and is intrinsically disadvantageous.

This however inhibits the polymerization for curing the ink and makes it difficult to form appropriate images.